Albert Barnes Commentary Mark 5:30

"And straightway Jesus, perceiving in himself that the power [proceeding] from him had gone forth, turned him about in the crowd, and said, Who touched my garments?" — Mark 5:30 (ASV)

Virtue had gone out of him: power to heal. The word in the original means power.

Who touched my clothes? He said this, not to obtain information (for he had healed her and must have known on whom the blessing was conferred), but he did it so that the woman herself might make a confession of the whole matter, by which the power of her faith and the greatness of the miracle might be manifested, to the praise of God.